Carton flap folder

ABSTRACT

A machine for folding the leading and trailing flaps of cartons being advanced one by one by a chain along a predetermined path. The leading flaps are folded by a wheel with a number of retarders spaced about the periphery of the wheel. The wheel turns to bring a retarder into intersecting relation with the path of each carton ahead of the leading flap. When in intersecting relation with the path, the retarder moves in the flow direction of the cartons but at a slower speed. The leading flap thus catches up with the retarder and is engaged by the latter. Due to the difference in speed, the carton passes by the retarder, and the leading flap is folded. The wheel is rotated in timed relation with the advance of the cartons by a drive directly connected to the drive for a cutter rotor which is rotated in timed relation with the advance of the cartons. The trailing flaps of the cartons are folded by a folding rotor which is driven in timed relation with the advance of the cartons by the same drive chain which advances the cartons.

United States Patent [72] lnventors RichardC.Zimmer;

Robert F. Lense, both of Rockford, Ill.

[21] Appl. No. 835,035

[22] Filed June 20,1969

[45] Patented Aug. 31, 1971 [73] Assignee Riegel Paper Corporation NewYork, N.Y.

[54] CARTON FLAP FOLDER {1113,6UJU7 Primary Examiner-Travis S. McGeheeAttorney-Wolfe, Hubbard, Leydig, Voiit & Osann ABSTRACT: A machine forfolding the leading and trailing flaps of cartons being advanced one byone by a chain along a predetermined path. The leading flaps are foldedby a wheel with a number of retarders spaced about the periphery of thewheel. The wheel turns to bring a retarder into intersecting relationwith the path of each carton ahead of the leading flap. When inintersecting relation with the path, the retarder moves in the flowdirection of the cartons but at a slower speed. The leading flapthuscatches up with the retarder and is engaged by the latter. Due tothe difference in speed, the carton passes by the retarder, and theleading flap is folded. The wheel is rotated in timed relation with theadvance of the cartons by a drive directly connected to the drive for acutter rotor which is rotated in timed relation with the advance of thecartons. The trailing flaps of the cartons are folded by a folding rotorwhich is driven in timed relation with the advance of the cartons by thesame drive chain which advances the cartons.

PATENIEU was] 197i 39602.10?

sum 1 BF 3 CARTON IFILAIP FOLDER BACKGROUND OF THE INVENTION Thisinvention relates to a machine for folding flaps on cartons fromextended positions to folded positions as the cartons are advancedrapidly along a predetermined path.

SUMMARY OF THE INVENTION The primary object of the present invention isto fold the leading flaps of the rapidly advancing cartons gently at arelative rate of speed much slower than the advancement speed of thecartons to insure that all of the flaps are folded but not torn or bentout of shape.

It is a related object of the present invention to fold the leading flapof each carton gently by retarding the forward motion of the flap withrespect to the carton such that, while both are moving forwardly alongthe path, the carton moves faster than the flap, and the flap is foldedrearwardly.

It is a further object to accomplish the above by mounting a wheel withretarders spaced angularly around the periphery thereof to rotate andproject the retarders, one at a time, into intersecting relation withthe path of successive cartons ahead of the leading flap of each carton.The retarder in intersecting relation with the path moves in the samedirection as the respective carton but at a slower speed causing theleading flap of the carton to catch up with and be engaged by theretarder to fold the leading flap rearwardly during the advance of thecarton.

It is a more detailed object to form each retarder as a radiallyextending finger bent around to form a pocket which opens in theupstream direction of the path when the retarder is in intersectingrelation with the path so that the finger engages the leading flap andguides the flap into and then out of the pocket thus folding the flap asthe carton advances.

It is another object to drive the wheel carrying the retarders in timedrelation with the advance of the cartons by a direct power takeoff fromthe drive of a cutter positioned upstream of the wheel and used toseparate the cartons as the latter are advanced along the path.

It is an object to use a chain drive both to advance the car tons and todrive a folding rotor in timed relation with the advance of the cartonsto fold the trailing flaps of the cartons.

Other objects and advantages will become apparent from the followingdetailed description taken in connection with the accompanying drawings.

BRIEF DESCRIPTION OF TI-IE DRAWINGS FIG. I is a fragmentary elevation ofa machine embodying the novel features of the present invention.

FIG. 2 is a fragmentary plan view taken substantially along the line 2-2of FIG. 1.

FIG. 3 is a fragmentary elevation similar to FIG. I but with frameworkremoved for clarity and with parts shown in moved positions.

FIG. 4 is a fragmentary elevation similar to FIG. 3 but with the partsshown in still further moved positions.

FIG. 5 is a fragmentary elevation of the machine of FIG. I and showingthe folding of both the leading and trailing flaps ofa series ofcartons.

FIG. 6 is a fragmentary cross section of a portion of the machine shownin FIG. 5 and taken substantially along line 6 of FIG. 7.

FIG. 7 is a partial cross section taken substantially along line 7-7 ofFIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in thedrawings for purposes of illustration, the invention is embodied in anautomatic flap-folding machine operable to fold the lower hinged leadingflaps 10 (FIG. 1) and trailing flaps ll of cartons 12 as the cartons areadvanced continuously at a high rate of speed along a predeterminedpath. During their advance, the cartons are held in an upright positionby carton holders 13, the latter being attached to and carried by adrive chain 14. The cartons are of the type having hinges with aresilient memory normally causing the flaps to assume upright positionsprotecting downwardly from the cartons.

In this instance, a continuous sealing strip 115 (FIG. 4) is heat sealedto the open bottoms of the cartons 12 and across the leading flaps 10and trailing flaps 11 of each carton. To separate the cartons, thesealing strip is cut between the trailing flap of one carton and theleadlin g flap of the following carton. A cutter wheel or cutter rotor17 (FIG. 1) is mounted on an axle 18 (FIG. 2) to rotate about an axisextending laterally of and below the path of advancement of the cartons.The cutter rotor is formed with four arms 19 (FIG. 3) extending radiallyoutwardly from the axle and spaced angularly apart. Connected to the endof each arm is a cutter or cutting blade 20 which extends laterally ofthe path of carton advancement. The cutter rotor is positioned below thepath a distance such that the blades can be rotated into intersectingrelation with the path.

As the cartons 12 advance, the cutter rotor 17 rotates counterclockwise(FIG. 1) in timed relation to the advance of the cartons such'that oneof the blades 20 rotates up and into the space between adjacent cartonsthereby cutting the sealing strip 15 and separating the cartons. Thatis, the rotor is driven with a peripheral speed equal to the advancementspeed of the cartons and thus successive blades move between successivecartons and cut the sealing strip as the rotor turns. This sequence isshown in progressive steps in FIGS. 1, 3 and 4.

The axle 18 is journaled at one of its ends in a support plate 21 (FIG.2), and the other end of the axle is journaled in a gearbox 22. Througha series of gears within the gearbox, the axle is connected to anddriven by a drive shaft 241 (FIG. 1) which extends from and is supportedby a frame member (not shown) and the gearbox is pivoted on the driveshaft for swinging back and forth through a limited range about thelatter. To prevent the cutter rotor 17 from damaging a great number ofcartons 12 should the rotor jam, the rotor is adapted to be movedautomatically out of intersecting relation with the path if one of theholders l3 presses against a blade 20 of the rotor. For this purpose, apair of parallel rods 25 and 26 (FIG. 2) extend between and are fastenedrigidly to the support plate 21 and the gearbox 22 to join the gearboxand the support plate as a single unit for swinging movement togetherabout the drive shaft 24. This unit is urged in a clockwise directionabout the drive shaft by a spring-biased rod 28 (FIGS. 1 and 2) which ispivotally connected at one end portion to the support plate 211 at alevel below the axis of the drive shaft. As most clearly shown in FIG.1, a spring 29 is telescoped over the other end portion of the rod 28and is biased between a nut 30 on the end of the rod and an L-shapedplate 31 through one leg of which the rod extends slidably, the otherleg of the plate being bolted to a stationary frame member 32. If therotor should jam, the force of the cartons 12 being moved along the pathwill swing the unit counterclockwise about the drive shaft against theforce of the spring thereby to free the blades from the cartons. To holdthe unit against clockwise swinging which would result due to thespring, a screw 35 (FIG. ll) threaded into a plate 36 on the framemember 32 contacts the rod 26 and may be adjusted to change the normalposition of the unit.

When the sealing strip 15 is sealed to the cartons 12, the leading andtrailing flaps 10 and 11 are pressed upwardly to horizontally extendingpositions and project forwardly and rearwardly, respectively, from thecartons. Once the sealing strip has been cut, the flaps are free tospring downwardly toward their normal upright positions as a result ofthe resilient memory of the flap hinges. Due to a number of factors,however, the flaps may remain in nearly horizontal positions thus makingit difficult to engage and fold the flaps to closed positions over thebottoms of the cartons. For example, the memory of the flap hingesusually is weakened when uping strip. In addition, the strip itselfunderlies the flaps and tends to resist downward swinging of the latter.Any sticky product which may have accumulated around the flaps also maytend to keep the flaps in generally horizontal positions. The flaps thusmay remain positioned closely adjacent the holders l3 and, when thecartons are being advanced at high speeds, difliculties are encounteredin folding the flaps to closed positions without tearing or distortingthe flaps.

In accordance with the present invention, the advancement of the leadingflap of each carton 12 is retarded smoothly and gradually in a mannerwhich allows the leading flap to advance along the path but at a slowerspeed than the carton, and the leading flap is folded by being guideddownwardly from a forwardly extending horizontal position, through avertical position, and then rearwardly toward a rearwardly extendinghorizontal position as the carton moves past the flap due to thedifference in advancement speed between the carton and the flap. Forthese purposes, a wheel 40 (FIG. 1) with a number of retarders 41,herein four, on the periphery thereof is mounted to rotate about an axisextending laterally of and below the advancement path of the cartonssuch that the retarders are rotated counterclockwise (FIG. 1) one at atime into the path just ahead of the leading flap of an advancingcarton. The wheel is rotated with a peripheral speed less than theadvancement speed of the carton so that the leading flap catches up withand is engaged by the retarder which shows the advancement of the flapwhile guiding the latter first downwardly and then upwardly toward afolded position. With this arrangement, each leading flap is engaged andfolded slowly while the carton is being advanced at a high speedresulting in a gently folding action and the substantial elimination oftearing, ripping, etc. which normally occurs if the flap is engaged by astationary flap folder.

Extending upwardly at an angle in a downstream direction and attached tothesupport plate 21 by a pair of bolts (FIG. 1) is a support frame 43(FIG. 2) in which a drive shaft 45 is journaled, and the wheel 40 isrigid with one end portion of the drive shaft to rotate with the latter.The wheel is advantageously driven directly from the axle 18 of thecutter rotor 17 at the same angular speed as the rotor. To accomplishthis, a chain 46 (FIG. 2) is trained around a first sprocket 47 mountedon the axle and a second sprocket 48 mounted on the end portion of thedrive shaft 45 opposite the end portion on which the wheel 40 ismounted. As shown in FIG. I, the drive shaft 45 is located above theaxle l8 and thus nearer the path of advancement. Since the distance tothe carton path is shorter, the diameter of the wheel is less than thatof the cutter rotor causing the wheel, which is rotated at the sameangular speed as the rotor, to rotate with a slower peripheral speedthan the rotor. Since the peripheral speed of the rotor is equal to theadvancement speed of the cartons, the peripheral speed of the wheel isless than the advancement speed of the cartons.

Each retarder 41 in this instance is formed as a finger 49 (FIG. I)curved around to form a mouth or pocket 50 which when the retarder ispositioned in intersecting relation with the path, opens in an upstreamdirection. One retarder is rotated into intersecting relation with thepath of the cartons 12 just ahead of each leading flap 10. As theleading flap in its extended position advances along the path at theadvancement speed of the carton, the leading flap catches up with theretarder which is being rotated counterclockwise (FIG. 1) or away fromthe leading flap. Because the leading flap extends downwardly slightlybelow horizontal, the trailing edge of the finger 49 can engage theupper side of the flap and can guide the flap into the pocket 50. Thethickness of the trailing edge portion of the finger is relatively smalland, when the finger engages the leading flap, the trailing edge of thefinger is just barely below the bottom 51 (FIG. 1) of the body of thecarton to engage and draw the flap downwardly. One particular advantageto this arrangement is that while the downward angle that the leadingflap makes with the horizontal may be very small, as for the reasonsmentioned above, the finger will still engage the upper surface of theflap ensuring that no leading flap remains in an extended position. Byobserving the sequence of operation as depicted in FIGS. 1, 3 and 4, itwill be seen that, as the carton 12 catches up with and then passes theretarder 41, the leading flap 10 is guided downwardly into the pocket 50and then slides along the finger and is bent upwardly and rearwardlytoward a folded or closed position by the finger as the carton passesover the retarder.

Advantage is taken of the provision of the drive chain 14 to use thelatter additionally to fold the trailing flaps 11 by driving a foldingrotor 53 (FIG. 6) in timed relation with the advance of the cartons 12.As shown in FIG. 7, the folding rotor turns about a vertical axis apositioned laterally of the advancement path of the cartons. A bearinghousing 54 is fixed to the end of a cantilevered arm 55 which extendshorizontally from the frame 32. Within the bearing housing is a bearing56 in which a shaft 57 is journaled to rotate about the axis a, and awasher 58 is welded around the shaft near the upper end of the shaft toprevent the latter from falling through the bearing. Beneath the housing54, a sprocket 60 with a downwardly extending hub 61 is telescoped onand connected to the lower end portion of the shaft by a splinedconnection. .Iournaled on the shaft beneath the hub is a disc 62 and,beneath the disc, a retainer plate 63 abuts the end of the shaft. Ascrew 64 extends through the retainer plate and intothe end of the shaftto hold the plate, hub, and disc on the shaft. Three screws 65 (twoshown in FIG. 7) extend upwardly through and lock the retainer plate,the disc and into the hub together thus causing the disc to rotate withthe hub and sprocket.

Onthe periphery of the sprocket 60 is a series of teeth 66 (FIG. 6)which engage the drive chain 14 causing the sprocket to be rotated witha peripheral speed equal to the advancement speed of the cartons 12.Four radially extending folding blades 67 are angularly spaced atintervals about the periphery of the disc 62 and, as the disc turns inresponse to rotation of the sprocket by the drive chain, these bladesare swung one at a time into intersecting relation with the path of theadvancing cartons. With the folding rotor 53 located laterally of thepath on the same side of the path as the drive chain, the distance fromthe shaft 57 to the path is greater than the distance from the shaft tothe drive chain.

With the above arrangement, the folding blades 67 move with a greaterspeed than the advancement speed of the cartons 12 causing each blade toovertake the carton immediately ahead of that blade when the latterenters the path. The folding blade thus catches up with, engages, andfolds the trailing flap ll forwardly as the blade moves through thepath, and this is accomplished gently because. the differential in thespeed of the folding blade and the carton is relatively small. To ensurethat each blade enters the path just behind a carton, the angularposition of the disc 62 can be adjusted with respect to the sprocket 60.A series of arcuate slots 68 (FIG. 6) are formed in the disc at thelocation for each screw 65. Before the screws are tightened to join theretainer plate 64, the disc 62, and the sprocket 60, the disc can beshifted angularly with respect to the sprocket to the extent of theslots.

This arrangement can be varied somewhat but, as shown here, the foldingrotor 53 is located immediately downstream of the wheel 40. Justdownstream of the folding rotor is a plow 70 (FIG. 5) which forces thefolded leading flaps l0 and trailing flaps ll tightly up against thebottoms 51 of the cartons 12.

From the above, it will be observed that the provision of the wheel 40moving the retarders 41 one at a time into intersecting relation withthe path of the advancing cartons 12 with the retarders moving in thesame direction as the cartons when the retarders are in the path but ata slower speed to retard the leading flaps 10 and fold the latter is aparticularly advantageous arrangement. This arrangement makes itpossible to fold the leading flaps gently at a differential speed muchless than the advancement speed of the cartons. For easy powertransmission and simple, effective timing of the rotation of-the wheel,the latter is driven directly off the drive for the cutter rotor 17.Another advantageous arrangement is the utilization of the drive chain14 not only to advance the cartons but also to rotate the folding rotor53 in timed relation to the advance of the cartons to fold the trailingflaps 11.

We claim as our invention: V

1. In a machine for rearwardly folding the hinged leading flap of acarton from an extended position to a folded position as the carton isadvanced along a preselected path with the flap projecting from thecarton and disposed in said extended position, the combination of, asupport, mechanism on said support for advancing the carton at apredetermined speed along said path, a wheel journaled on said supportto turn about an axis spaced from and extending transversely of saidpath, a retarder on the periphery of said wheel and rotatable intointersecting relation with said path and ahead of the leading flap as anincident to rotation of the wheel, and means for rotating said wheel tomove the retarder in the same general direction as the leading flap whenthe retarder is disposed ahead of the flap but at a speed less than thespeed of the carton whereby the leading flap catches up with and isengaged by the retarder and is gradually folded rearwardly duringadvancement of the carton along said path, said retarder being a fingercurved around to form a pocket which opens in a direction upstream ofsaid path when said retarder is disposed in intersecting relation withsaid path so that said finger can engage said leading flap and guide thelatter into said pocket to fold the flap as the carton advances alongsaid path past retarder.

2. The machine of claim 11 in' which said mechanism for advancing thecarton includes a power-driven carrier chain, said machine furtherincluding means for folding the hinged trailing flap of said carton froman extended position in which the flap projects from the carton to afolded position as the carton is advanced along said path, saidlast-mentioned means comprising a folding rotor mounted to turn about anaxis perpen dicular to but laterally offset from said path, a foldingblade on said rotor and extending radially outwardly therefrom, saidcarrier chain being operably connected to said folding rotor to rotatethe latter and move said blade into intersecting relation with said pathin timed relation with the advance of said carton to engage saidtrailing flap and fold the latter from said extended position to saidfolded position.

3. The device of claim 2 in which said drive chain is positionedlaterally of said path, said axis of said folding rotor being positionedon the same side of said path as said chain, said folding rotorincluding a sprocket mounted to rotate about said axis and drivinglyengaged by said chain to rotate said sprocket with a peripheral speedsubstantially equal to the advancement speed of said carton and to causesaid blade to move with a speed greater than the advancement speed ofsaid carton whereby said blade is operable to enter said path behindsaid trailing flap and overtake said trailing flap to fold the latter.

4. In a machine for rearwardly folding the hinged leading flaps of aseries of connected cartons from extended positions to folded positionsas the cartons are advanced one by one along a preselected path at apredetermined speed with the flaps projecting from the cartons anddisposed in said extended positions, the combination of, a support, arotor journaled on'said support to turn about an axis spaced from andextending transversely of said path, cutters on the periphery of saidrotor and rotatable with the latter into intersecting relation with thepath for separating the cartons from one another, a drive mechanismconnected to said rotor to rotate said cutters with a peripheral speedsubstantially equal to said predetermined speed, a wheel journaled onsaid support downstream of said rotor to turn about an axis spaced fromand extending transversely of said path, retarders spaced angularlyabout the periphery of said wheel and rotatable with the wheel intointersecting relation with said path, drive means connected between saiddrive mechanism and said wheel to rotate said wheel in timed relationwith said rotor to move each retarder ahead of one of the leadin fla sin timed relatlon with the advance of the cartons an in t e same generaldirection as the leading flap when that retarder is disposed ahead ofthe flap, and said drive means being operable to rotate said wheel witha peripheral speed less than the speed of said cartons whereby theleading flap of each carton catches up with and is engaged by one of theretarders and is folded rearwardly as such carton is advanced along saidpath.

5. In a machine for rearwardly folding the hinged leading flaps ofsuccessive cartons from extended positions to folded positions as thecartons are advanced in spaced relation along a preselected path withthe flaps projecting from the cartons and disposed in said extendedpositions, the combination of, a support, mechanism on said support foradvancing the cartons at a predetermined speed along said path, afolding wheel journaled on said support to turn about an axis spacedfrom and extending transversely of said path, a series of angularlyspaced fingers and intervening pockets formed around the periphery ofsaid wheel, said fingers being rotatable into intersecting relation withsaid path and ahead of the leading flaps of successive cartons as anincident to rotation of said wheel, each of said pockets opening out ofthe peripheral surface of said wheel and receiving one of said flapswhen the finger ahead of the pocket is positioned ahead of such flap,and means for rotating said wheel to move each finger in the samegeneral direction as the respective flap when the retarder is disposedahead of such flap but at a speed less than the carton whereby the flapcatches up with and is engaged by the finger and is gradually foldedrearwardly during advancement of the carton along said path.

a. In a machine for folding the hinged flaps of successive cartons asthe cartons are advanced in spaced relation along a predetermined path,the combination of, a support, a powerdriven chain on said support foradvancing said cartons along said path, a folding rotor mounted to turnabout an axis perpendicular to but offset from said path, angularlyspaced folding blades on said rotor and extending radially outwardlytherefrom, a sprocket fastened to and coaxial with said rotor and havingits periphery located radially inwardly of the free ends of said blades,and said chain extending tangentially of and meshing with said sprocketto rotate said rotor and move said blades into intersecting relationwith said path in timed relation with the advance of the cartons wherebysaid blades engage and fold said flaps.

1. In a machine for rearwardly folding the hinged leading flap of acarton from an extended position to a folded position as the carton isadvanced along a preselected path with the flap projecting from thecarton and disposed in said extended position, the combination of, asupport, mechanism on said support for advancing the carton at apredetermined speed along said path, a wheel journaled on said supportto turn about an axis spaced from and extending transversely of saidpath, a retarder on the periphery of said wheel and rotatable intointersecting relation with said path and ahead of the leading flap as anincident to rotation of the wheel, and means for rotating said wheel tomove the retarder in the same general direction as the leading flap whenthe retarder is disposed ahead of the flap but at a speed less than thespeed of the carton whereby the leading flap catches up with and isengaged by the retarder and is gradually folded rearwardly duringadvancement of the carton along said path, said retarder being a fingercurved around to form a pocket which opens in a direction upstream ofsaid path when said retarder is disposed in intersecting relation withsaid path so that said finger can engage said leading flap and guide thelatter into said pocket to fold the flap as the carton advances alongsaid path past retarder.
 2. The machine of claim 1 in which saidmechanIsm for advancing the carton includes a power-driven carrierchain, said machine further including means for folding the hingedtrailing flap of said carton from an extended position in which the flapprojects from the carton to a folded position as the carton is advancedalong said path, said last-mentioned means comprising a folding rotormounted to turn about an axis perpendicular to but laterally offset fromsaid path, a folding blade on said rotor and extending radiallyoutwardly therefrom, said carrier chain being operably connected to saidfolding rotor to rotate the latter and move said blade into intersectingrelation with said path in timed relation with the advance of saidcarton to engage said trailing flap and fold the latter from saidextended position to said folded position.
 3. The device of claim 2 inwhich said drive chain is positioned laterally of said path, said axisof said folding rotor being positioned on the same side of said path assaid chain, said folding rotor including a sprocket mounted to rotateabout said axis and drivingly engaged by said chain to rotate saidsprocket with a peripheral speed substantially equal to the advancementspeed of said carton and to cause said blade to move with a speedgreater than the advancement speed of said carton whereby said blade isoperable to enter said path behind said trailing flap and overtake saidtrailing flap to fold the latter.
 4. In a machine for rearwardly foldingthe hinged leading flaps of a series of connected cartons from extendedpositions to folded positions as the cartons are advanced one by onealong a preselected path at a predetermined speed with the flapsprojecting from the cartons and disposed in said extended positions, thecombination of, a support, a rotor journaled on said support to turnabout an axis spaced from and extending transversely of said path,cutters on the periphery of said rotor and rotatable with the latterinto intersecting relation with the path for separating the cartons fromone another, a drive mechanism connected to said rotor to rotate saidcutters with a peripheral speed substantially equal to saidpredetermined speed, a wheel journaled on said support downstream ofsaid rotor to turn about an axis spaced from and extending transverselyof said path, retarders spaced angularly about the periphery of saidwheel and rotatable with the wheel into intersecting relation with saidpath, drive means connected between said drive mechanism and said wheelto rotate said wheel in timed relation with said rotor to move eachretarder ahead of one of the leading flaps in timed relation with theadvance of the cartons and in the same general direction as the leadingflap when that retarder is disposed ahead of the flap, and said drivemeans being operable to rotate said wheel with a peripheral speed lessthan the speed of said cartons whereby the leading flap of each cartoncatches up with and is engaged by one of the retarders and is foldedrearwardly as such carton is advanced along said path.
 5. In a machinefor rearwardly folding the hinged leading flaps of successive cartonsfrom extended positions to folded positions as the cartons are advancedin spaced relation along a preselected path with the flaps projectingfrom the cartons and disposed in said extended positions, thecombination of, a support, mechanism on said support for advancing thecartons at a predetermined speed along said path, a folding wheeljournaled on said support to turn about an axis spaced from andextending transversely of said path, a series of angularly spacedfingers and intervening pockets formed around the periphery of saidwheel, said fingers being rotatable into intersecting relation with saidpath and ahead of the leading flaps of successive cartons as an incidentto rotation of said wheel, each of said pockets opening out of theperipheral surface of said wheel and receiving one of said flaps whenthe finger ahead of the pocket is positioned ahead of such flap, andmeans for rOtating said wheel to move each finger in the same generaldirection as the respective flap when the retarder is disposed ahead ofsuch flap but at a speed less than the carton whereby the flap catchesup with and is engaged by the finger and is gradually folded rearwardlyduring advancement of the carton along said path.
 6. In a machine forfolding the hinged flaps of successive cartons as the cartons areadvanced in spaced relation along a predetermined path, the combinationof, a support, a power-driven chain on said support for advancing saidcartons along said path, a folding rotor mounted to turn about an axisperpendicular to but offset from said path, angularly spaced foldingblades on said rotor and extending radially outwardly therefrom, asprocket fastened to and coaxial with said rotor and having itsperiphery located radially inwardly of the free ends of said blades, andsaid chain extending tangentially of and meshing with said sprocket torotate said rotor and move said blades into intersecting relation withsaid path in timed relation with the advance of the cartons whereby saidblades engage and fold said flaps.